Twisting mechanism



April 14, 1931. M DURAND 1,800,784

TWISTING MECHANISM Filed Oct. 30. 1928 2 Sheets-Sheet l April 14, V 1931.

M. P. DURAND TWISTING MECHANISM 2 Sheets-Sheet 2 Filed 001;. 30, 1928 Maeca P/wL flq/m/va Q Qv.

flTTOR/VEV Patented Apr. 14, 1931 UNITED :STATES PATENT OFFICE TWISTING MECHANISM Application filed October 30, 1928, Serial No. 315,991, and in France November 3, 1927.

The present invention relates to mechanism for twisting threads or yarns of the kind in which the material worked forms a loop' about the rotary part and envelopes in its rotation the thread supply disposed at the centre.

In such mechanism the rotary member must have a complex arrangement to ensure immobility of the thread supply or its Totation in a direction opposite to that of the rotary member carrying the thread loop.

The present invention has for its object to provide an improvement, in this mechanism, consisting essentially in a balanced magnetic arrangement in the air gap through constituted by a magnet and a iron or other magnetic material.

which passes the thread, which, in its rotation, surrounds the central feed device. If the central feed device is merely held stationary, the magnetic arrangement may be mass of soft If, on the contrary, the feed-device must rotate, the magnetlc arrangement will comprise inductors arranged exteriorly of the thread loop,

and a rotor which, fixed to the supply device,

ples of the ing part of the spindle.

transmits to it its movement of rotation.

In the drawings, Fig. 1 represents an elevational view, partly in section, of a thread twisting mechanism embodying the principresent invention;

Fig. 2 depicts a side elevation of a modified embodiment of my invention; and

Fig. 3 illustrates a sectional view taken on the hue a-a of Fig. 2. 1

Fig. 1 shows an embodiment of the invention allowing of holding the thread-carrier stationary. In this case it will easily appear that the main advantage of the arrangement is the equilibration of the magnetic force acting at each end of the bar of soft iron or other magnetic material rigid with the central part, this obviating all lateral rubbing of the central part on the tubular rotat- However, this equilibration of the magnetic force cannot be obtained except with perfect regulation of the air gap between each of the ends of the soft iron bar and the arms of the magnet. Even if-this re lation is correct at the start, it may be 'tion on w-a of Fig.

8. tered by the play resulting from g the wear on the rubbing surfaces, from which results a lateral force liable to cause an increase of the necessary driving force and of the couple tending to drive the central part.

The form of construction shown i n the annexed Figures 2 and 3 obviates this disadvantage, and shows a more logical use of the movement of the magnet when the field circuit is no longer closed by the soft iron bar. In this case the Weight of the magnet, and, if desired, its attractive force on a bar are utilized to cause simultaneously the uncoupling of the spindle drive, its braking, and the uncoupling of the thread drive or only one or two of these movements.

In Fig. 1, the central feed device is constituted of the bobbin 1 carrying the thread 2 which passes through a central orifice 3 within the bobbin, and then passes through the interior of the rotary tube 4 to issue by the opening 5 to pass over the flyer 6 rigid with the rotary tube 4, from which it is drawn by rollers 7, 7 On the bobbin 1 is fixed a bar 8 of soft iron or other magnetic material, pierced at the middle of its length to allow passage of the tube 4, and outside the thread are disposed the poles of a magnet 9, so arranged that the bar 8 is held fixed by the attraction of the magnet notwithstanding the rotationof the tube 4, on which the bobbin 1 rests. If desired, the magnet 9 can be so arranged that if the bar 8 does not close the magnetic circuit, its arms tend to fall into the position 9 where one of them acts on a bell crank lever 10 pivoted at 11 on the fixed part, and carries a projection 12 forming a brake on the pulley 13 rigid with 4. An apparatus is thus provided with a braking system which functlons automatically if, for any reason, the tube 4 drives the bobbin 1 and the bar 8, which may take place, for example, on tangling of the threads.

In Figs. 2 and 3 (the latter being a sec- 2, the spindle being turned a quarter of a revolution), the arms of the magnet 9' are disposed under the dovi lnwardly bent ends of the bar 8' rigid wit 1.

The fiyer 6 passing in the magnetic field is preferably constituted by insulating material such as vulcanized fibre.

If, for any cause, the bar turns and opens the magnetic circuit holding the branches of the magnet 9' in the'position shown, these fall under their own weight and one of them acts on a bell crank lever 10 pivoted at 11' on a fixed part of the device applying the brake shoe 12 on the pulle 13 rigid with the tube 4. The arms of t e magnet 9 on falling also act on the end 14 of an uncoupling lever 15,;v11ich causes the tensiomng pulley 16 carried by 15 to fall and thus release the grip of the cord 17 on the driving wheel 18 of the pulley 13 and also to stop the drive of the thread 2 by the roller 7 For this purpose the roller 7 a is mounted at the end of a fork 19 pivoted at 20 on a fixed part and normally applied against the roller 7 by a counterweight 21. A rod 22 connects the fork to the lever 15 so that when the lever 15 is lowered, the roller 7 8 is separated from 7 To ensure the action of the uncoupling and braking mechanism the fixed part is provided with a bar 23 of magnetic material, in proximity to which the arms of the magnet 9 fall when the bar 8' no longer closes the field circuit. The attraction of the bar 23 on the magnet 9 is added to the action of the weight to cause actuation of the uncoupling and braking mechanism. I H

In the construction shown the bobbin 1 rests on the-rotatable tube 4., through the intermediary of a tube 24 and a hemispherical bearing 25, the lubrication of which is ensured constantly by the oil bath contained 111 well 26 which is rigid with 4'. The bearing 25 permits oscillation of 1 with respect to 4, to allow the flexibility necessary to eliminate the vibrations at critical eriods, without this movement being allowe to var the air gap between 8 and 9', the surfaces 0" the two ends of the bar 8' being hemispherical, with the centre thereof coinciding with the point of oscillation of the bearing 25.-

It will be understood that the arrangements described and shown are only given by way of example, and can be varied to a large extent.

What I claim is 1. In a twisting mechanism of the character set forth, and in combination, a rotatable spindle, a fiyer carried by said spindle,

a thread carrier loosely mounted on said spindle, brake mechanism for arresting the rotation of the spindle, a magnetic memberv attached to said thread carrier a magnetic means associated with said magnetic member and located exteriorly of said fiyer for holding the thread carrier in restraint, said magnetic means comprising a magnet arranged and adapted to fall by gravity and operate said brake mechanism on failure of magnetic attraction between the magnet and, the magnetic member associated therewith.

2. A twisting mechanism as claimed in claim 1, in which the magnet is mounted on a horizontal axis and so located that in the ordinary operation of the mechanism the magnet wi1l,be held in a horizontal position by magnetic attraction of the bar, said magnet and bar being spaced apart to allow the free assage therebetween of the. filament to e wound, said magnet being arranged and adapted to drop at its free end upon cessation of magnetic attraction and operate the brake mechanism by its superimposed weight thereon.

3. In a twisting mechanism of the character set forth, the combinationcomprising a hollow rotatable spindle having a hemispherical bearing at its upper free end, a

thread outlet at its lower end, a fiyer secured to said spindle adjacent to said thread outlet, a central thread carrier mounted on the hemispherical bearing of said spindle and having a hollow central conduit communicating with the centre of said spindle, whereby the thread carrier is free 'to oscillate slightly on said bearing a magnetic body fixedly fastened to-the lower part of said thread carrier, and a horse-shoe magnet located exteriorly ofthe spindle and of the fiyer and having the poles thereof encompassing the said magnetic body.

MARCEL PAUL DURAND. 

